I. Field of the Invention
The present invention relates generally to refrigeration systems and heating systems for consumable products, and particularly, controlling the temperature of such systems to maximize energy conservation.
II. Description of Related Art
Beverage coolers are utilized throughout the world to provide cost effective delivery of consumable products in retail stores, outlets and other public distribution points (hereafter collectively referred to as retail stores). Beverage coolers utilize cooling devices to maintain the product at a serving temperature below the ambient temperature. The cooling devices typically includes a compressor to compress a refrigerant and an evaporator to evaporate the refrigerant, as is well known. These refrigerated beverage coolers require energy to operate so it is desirable that a product for sale be maintained at one temperature during business hours and maintained at a second temperature higher than the first temperature during non-business hours to conserve energy. For example, a retailer will set a beverage cooler to operate at 3xc2x0 Celsius (C) during business hours and 10xc2x0 C. during non-business hours. Accordingly, the retailer has lower energy expenditures than if the retailer set the cooling device at 3xc2x0 C. at all times.
One technique to vary the cooling device""s temperature is for the beverage cooler to be manually adjusted at the beginning and ending of a business day. Manual adjustment is usually performed by an employee, but is sometimes not done due to the employee""s forgetfulness. Also, it may take 30 minutes or more to bring the contents to a serving temperature so the product may not be at the desired serving temperature when the retail store opens. More advanced systems utilize a clock to trigger the change in operation temperature, though this may be problematic if the store has different hours of operation for different days of the week, if the store changes its business hours, or if the time changes seasonally. Yet other systems utilize motion detectors to determine customers are in the vicinity of the beverage cooler, and if so, maintains the normal operating temperature of the beverage cooler.
Likewise, vending machines that serve warm or hot beverages or food may suffer from similar deficiencies in energy management. In order to maintain the beverage or food at its serving temperature (e.g., above ambient), the appliance may continuously actuate the heating device of the appliance or may utilize manual or clock controlled systems for actuating the heating device at various times throughout a day or week.
Thus, there exists an unsatisfied need in the industry for a beverage cooler that is optimized for energy efficiency and product quality, and that is fully automated.
The present invention provides systems and methods for temperature control in refrigeration systems, such as beverage coolers, or heating systems such as coffee dispensers, so as to optimize functional performance and energy savings. The present invention learns the usage and/or activity patterns associated with a refrigeration system or heating system (hereafter generally referred to as an appliance) and actuates the temperature control device (e.g., a cooling device or heating device) to maintain an optimal operating temperature during periods of use or activity (e.g., when the retail store where the appliance is located is open for business) and actuates the temperature control device to maintain an optimal energy-saving temperature during periods of non-use or inactivity (e.g., when the retail store is closed). The use or activity is determined utilizing a use sensor, which may include one or more of a motion detector, door sensor, product purchase, vibration detector or any other suitable devices for monitoring or sensing activity or use associated with the appliance. The usage and/or activity over a period of time is recorded and then an optimal schedule for actuating the heating and/or cooling device for regular and energy-saving operations is determined and implemented. The usage and/or activity is continuously monitored and should it change, then the present invention will modify the schedule of actuating the heating and/or cooling device accordingly.
In accordance with an aspect of the present invention, a control unit of a refrigeration system in accordance with the present invention receives and records activity data such as door openings and/or human presence detection and/or product purchase in the vicinity of the refrigeration system, and then establishes the beginning and end times of an energy saving mode for the refrigeration system over a period of time, such as a week. The control unit calculates the time to restart the compressor cycle at the end of the energy saving mode so that the product will be at the correct temperature at the time of first usage. As part of the energy saving function, the lamps in the refrigeration system are turned off and on again by the control unit according to the activity data. Once the control unit implements an energy saving mode schedule based on usage patterns, no hourly or daily monitoring is required to provide a product at the correct temperature during business hours of the retail store. Advantageously, the control unit is not dependent on real time, but activity, and therefore can be used in every global time zone. In addition, the usage data collected by the control unit can be used by the retail store to determine traffic patterns in the vicinity of the beverage cooler.
An embodiment of the present invention provides for a system for controlling an appliance, wherein the appliance comprises a temperature control device, the system comprising a use sensor that generates a signal based on the use of (or activity associated with) the appliance, and a control unit that is in communication with the use sensor and that generates a control signal to be provided to the temperature control device, wherein the control signal is based at least partially on historical signals received from the user sensor. The use sensor may comprise an activity sensor for deterring human activity in the proximity of the appliance and/or a human presence detector. The human presence detector may comprise at least one of a motion detector, an infrared sensor and a vibration detector. The appliance may include a storage compartment accessible by a door, and in such instances, the use sensor may comprise a door sensor.
In addition, the control unit may store a plurality of signals received from the use sensor, and then determine a usage pattern for the appliance based on the stored signals. The control unit may then determine a schedule for implementing an energy saving mode of operation for the appliance based on the usage pattern. The appliance may also include operating lights, and wherein the control unit controls the operation of the lights according to the historical signals.
Another embodiment of the present invention provides a system for controlling a refrigeration system, wherein the refrigeration system comprises a storage compartment accessible by a door and a cooling device, the system comprising a human presence detector that generates first signals based on the presence of a human in a proximity of the detector, a door sensor that generates second signals based on openings of the door, and a control unit that is in communication with the human detector and door sensor and that generates a control signal to be provided to the cooling device, wherein the control signal is based at least partially on a historical first and second signals received from the human detector and door sensor.
Yet another embodiment of the present invention provides a method for controlling a refrigeration system, wherein the refrigeration system comprises a cooling device, the method comprising receiving human detector status signals from a human detector based on the presence of a human in a proximity of the human detector, receiving door open signals from a door sensor based on the opening of a door of the refrigeration system, and controlling the cooling device based on a control signal, wherein the control signal is based at least partially on historical human detector status and door open signals received from the human detector and door sensor.